One of the men went behind the pharmacy counter, and took a quantity of medication from a safe.

A male suspect takes medication from a safe at a Sarnia Pharmacy on Dec. 6, 2017. (Sarnia Police)

Both men fled on foot.

There was only one employee in the store at the time, and he was not injured.

The first suspect, who brandished the knife, appears to be a taller, heavy set male wearing a black winter coat, jeans, balaclava and gloves.

The second suspect also appears to be tall, but not as big as the first suspect. This male wore a dark hoodie with a distinctive white faced Halloween pumpkin design on the front of the sweater and dark wind pants with a white designed stripe along the leg.

Anyone with information about the robbery is asked to call the Sarnia Police Criminal Investigations Branch, 519-344-8861 ext. 5300 or Crime Stoppers.